Alexander Thomas Dick 1911-1982

Alexander Thomas Dick
- Alick to his friends-was born in Melbourne on 9 February 1911
and died in Adelaide on 3 July 1982.

He was the second son of John Laird Dick who was born in Glasgow,
Scotland in 1874 and came to Australia in 1888 with two older
brothers. They settled in Victoria where Dick's father, who was
employed in the Victorian civil service, married Florence Mary
Smith, born in Victoria of English parents. They had four children
of whom Alick was the second, having an elder brother, who also
became a chemist, and two younger sisters. Alick married Gwendda
Muriel Harwood on 18 January 1946. They had two children, a son,
Ian Robert and a daughter, Anne Elizabeth, both of whom are graduates
of the University of Adelaide.

Dick's education began at South Yarra State School, Melbourne,
from which he proceeded to Melbourne Church of England Grammar
School where he reached matriculation standard in 1927. The subjects
he studied included mathematics, chemistry and physics.

In 1928 he joined the Mount Lyell Chemical Works as a 'chemical
cadet' but then spent fifteen months as a clerical officer awaiting
a vacancy at the firm's Yarraville works. As this did not materialize
he joined the laboratory staff of Francis Longmore and Co. in
1929 as assistant to the works manager and chief chemist at the
firm's food products factory in West Melbourne.

While those two years afforded little useful experience or satisfaction,
Dick took advantage of them by attending an evening course at
Melbourne Technical College, at the completion of which he obtained
the Public Analyst Certificate. There is no doubt that this analytical
background later contributed substantially and effectively to
Dick's approach to his research.

In 1930 he commenced a science course at the University of Melbourne,
studying Chemistry, Physics, Botany, and Zoology in his first
year; Chemistry (II), Biochemistry and Physiology, and Bacteriology
in his second year; and Chemistry (III), Biochemistry and Physiology
(II) and Bacteriology (II) in third year. He obtained honours
in all subjects, his lowest position in the class lists being
fourth.

With this background Dick applied for a position with the Council
for Scientific and Industrial Research. In this he was successful,
being appointed as a Junior Research Officer to the Animal Health
Research Station, Townsville, where he took up duty on 9 January
1933. There he worked for five years with A.W. Turner
(later FAA) on the investigation of contagious bovine pleuropneumonia.
Those investigations were largely concerned with the biochemical
and immunological properties of the causal organism and its metabolic
requirements for growth in artificial media. The work resulted
in the development of a vaccine that was largely instrumental
in bringing this disease under control in Australia.

Dick demonstrated early in his career a useful administrative
capacity that was soon recognised by his being given technical
and administrative responsibility for a field station, 'Helenslee',
west of Charters Towers. He was also given in 1936 administrative
responsibility for the research station at Townsville and in 1937
supervised its closing down, the handing over of its activities
to the Queensland Department of Agriculture and the transfer of
the CSIR staff and equipment to Melbourne.

Parkville

On his return to Melbourne, Dick was appointed Officer-in-Charge
of the Chemical Pathology Section of the Division of Animal Health
and Production based at the Parkville Laboratory under the direction
of the then Chief of Division, L.B. Bull.
For some years considerable sheep losses had been suffered in
southern New South Wales and northern Victoria due to what came
to be called 'toxaemic jaundice', and Bull was chairman of a committee
directing a co-operative investigation into this problem. Dick
was immediately involved in work relevant to toxaemic jaundice
and was co-author of A Preliminary Note on the Aetiology of
Enzootic Jaundice, or "Yellows" of Sheep in Australia
with Albiston, Bull and Keast. It was concluded that enzootic
jaundice was due to a disturbance of copper metabolism associated
with high storage values for copper in the liver and a sudden
mobilisation of copper into the blood stream; that is, the disease
was, at bottom, chronic copper poisoning. Dick's involvement in
this programme was extensive and played a major part in unravelling
the complex situation that was revealed. The story has been summarised
briefly by Bull (Victorian Veterinary Proceedings, 1963-64,
17-20) who wrote: 'The CSIR Division had formed a Section of Chemical
Pathology with Mr A.T. Dick in charge and thus prepared itself
for an investigation which depended very much upon applied chemistry
for success'. The validity of that statement is made clear later
in Bull's review when he shows that they were concerned with three
types of chronic copper poisoning in sheep, the first due to excess
intake of copper usually from contaminated food or pasture the
second to liver damage produced most commonly by the consumption
of plants containing pyrrolizidine alkaloids (caused, in the investigation
in question, by the ingestion of Heliotropium europaeum), the
third to mineral or inorganic imbalance resulting from a diet
low in molybdenum and inorganic sulphate.

It is to this third category that Dick made his major scientific
contribution. The discovery of the metabolic interrelation of
molybdenum, copper and sulphate represented a significant contribution
to knowledge and, to quote one authority, 'initiated a new era
in trace element nutrition in which the significance of mineral
interrelations has been highlighted in a dramatic way and stimulated
a remarkably large series of similar types of study overseas'.
of Dick's twenty-six papers published during this period, some
were concerned with techniques, a no. with the development
of analytical methods and the acquisition of data, and a substantial
proportion to the effects of inorganic sulphate on molybdenum
and copper metabolism in sheep.

It is appropriate at this point to acknowledge, as Dick would
have wished, the skilled assistance of J.B. Bingley in both the
extensive analytical work involved in the investigation and in
the development of improved analytical techniques.

Dick and Bull reported in 1945 the first observations on the effects
of molybdenum in the diet of ruminants in limiting the accumulation
of copper in their tissues. Further observations by Dick indicated
that there was a third factor involved which materially altered
the control by molybdenum of copper accumulation, and this was
identified as inorganic sulphate. He also showed that sulphate
regulated molybdenum excretion in the urine and hence the level
of molybdenum in circulating blood. The story was completed in
what was Dick's last publication which postulated that sulphate
is reduced to hydrogen sulphide which reacts with molybdates to
form thiomolybdates. These combine with copper to form insoluble
copper thiomolybdates thereby limiting the absorption of dietary
copper.

Reference has been made to the role of Heliotropium europaeum
in toxaemic jaundice. Bull and Dick were aware that a fatal
liver disease of human beings in the USSR, due to consumption
of grain contaminated with seed of Heliotropium lasiocarpum,
was due to the presence in H. lasiocarpum of two alkaloids
of the pyrrolizidine group, heliotrine and lasiocarpine. They
arranged for a study of the alkaloids of H.europaeum
first at the Department of Pharmacology, University of Melbourne,
and then at the CSIR Division of Industrial Chemistry. The same
two alkaloids, heliotrine and lasiocarpine, were shown to be present.
At about this time, a committee was formed to investigate the
so-called Kimberley Horse Disease that occurred on the cattle
stations of northwestern Australia, and Bull's studies of the
liver lesion involved convinced him that it resembled the pyrrolizidine
alkaloidosis caused by Heliotropium europaeum. The horses
were known to feed on Crotalaria species, of which Crotalaria
retusa had been shown in the USA to contain a pyrrolizidine
alkaloid, monocrotaline, that caused chronic liver disease.

An intensive study developed of pyrrolizidine alkaloids, their
mode of action in giving rise to liver damage and their chemistry,
involving Bull, Dick and C.C.J. Culvenor, an organic chemist in
the CSIR Division of Industrial Chemistry. It is difficult now
to sort out the individual contributions of Bull and Dick. Bull
was unquestionably the pathologist and the leader, but given his
heavy commitments as Chief of Division, it is probable that the
driving force behind the experimental programme in the Division
of Animal Health, maintaining its momentum and encouraging and
integrating the work of the several collaborators, was Dick. Certainly
he undertook the intensive testing of other pyrrolizidine alkaloids
that established structure-activity correlations and made possible
the prediction of the toxicity of other Australian plants containing
the alkaloids. In due course the programme broadened in scope
to include such plants as Echium, Crotalaria and Senecio
species and took in aspects such as pharmacology and metabolism.
The study of rumen metabolism of the alkaloids (initiated by A.T.
Dann) was illuminating and led to the identification by Culvenor
of l-methylene pyrrolizidine as a non-toxic metabolite formed
by an unusual reductive rearrangement. This led in turn to the
recognition that the alkaloids had alkylating properties, which
could account for their nucleo-toxic effects, and to the finding
by Dick that the metabolic conversion of the alkaloids to 1-methylene
pyrrolizidine could be promoted, in rumen liquor in vitro,
by the addition of Vitamin B12, a point that he followed up
vigorously. Dick's direct participation in this extensive and
complex programme came to an end in 1965 when he was appointed
Chief of the CSIRO Division of Nutritional Biochemistry in succession
to H.R. Marston but not before the collaboration had led to the
publication of the definitive text, The Pyrrolizidine Alkaloids,
their Chemistry, Pathogenicity and other Biological Properties,
by Bull, Culvenor and Dick. It may be not unreasonable to
suggest that part of Dick's contribution to this successful collaboration
was as a communication link between Bull the biologist and Culvenor
the organic chemist. Arising from the pyrrolizidine programme
Dick was co-author of eight scientific papers, mostly in collaboration
with Bull and largely concerned with the effects of pure alkaloids
on experimental animals.

In his career at Parkville, Dick displayed several characteristics
that were to prove significant in his work as Chief of the Division
of Nutritional Biochemistry. One of his former colleagues at Parkville
described him as 'Platonic in argument' and added that it was
a great delight to listen to discussions that were stimulating
in their excellence. I myself had some experience of such discussions
between Dick and Bull and believe that they contributed substantially
to the clarification of ideas and so to the solution of research
problems. Dick' s unyielding tenacity in argument when he believed
his point to be valid was coupled with scrupulous honesty and
lack of compromise in his dealings both with others and with himself.
He was reserved but firmly fixed in his attitudes and was always
prepared to take a lead in raising difficult and controversial
issues. When he became aware of personal matters touching the
welfare of those about him, he involved himself unobtrusively,
with understanding and counsel. He was a good organiser who always
gave full recognition to the contributions of his co-workers and
supporting staff.

Adelaide

The Division for which Dick became responsible in 1965 presented
a situation different from that of the Parkville laboratory. His
predecessor had been an autocrat who had both generated and supervised
the divisional research programmes on a day-to-day basis. Dick
introduced a more democratic style of management and brought about
a no. of improvements in laboratory facilities including an
increased ratio of technical to scientific staff. He saw himself
as a 'facilitator' rather than a director. Nevertheless, as one
of his staff wrote, Dick's 'somewhat rigid outlook did, however,
lead to a critical assessment of divisional programmes and was
a considerable benefit to the staff, encouraging them also to
critically assess the directions and detailed procedures of their
research projects. He did not approve of laissez-faire attitudes
towards research and continually had in mind his perceived terms
of reference for divisional activities'. Research sections were
formed, each led by a senior scientist with a degree of autonomy,
and senior staff were involved in decisions on proposed research
programmes. Once a research proposal had been approved-often after
exhaustive and lengthy debate-Dick did not interfere with its
implementation.

Dick's perception of the terms of reference of his Division led
to increasing and better defined emphasis on particular biological
mechanisms. These included the metabolic interrelations of vitamin
B12 and folic acid in cobalt-deficient sheep, the role of copper
in brain development in the foetal lamb, the role of micro-organisms
in the fermentation process and their energetic efficiency, the
synthesis of S-amino acids in the rumen, the degradation of pyrrolizidine
alkaloids in the rumen and the involvement of tryptamine alkaloids
in the chronic poisoning of sheep by Phalaris tuberosa.

During his period as Chief, Dick's responsibilities were, of necessity,
largely administrative and his opportunities for advancing his
own research limited. He was, however, able to pursue his interests
in the pyrrolizidine alkaloids and the interaction between molybdenum,
sulphate and copper in the sheep; reference has already been made
to his work on the conversion of molybdates to thiomolybdates
with the consequent formation of insoluble copper thiomolybdates.
He retired in February 1976 and did not undertake any further
research.

Towards the end of Dick's tenure, the Executive of CSIRO approved
a major change in the objectives of the Division, namely to move
into the study of human nutritional problems, at the expense of
existing programmes on ruminant nutrition. This change in direction
was in no sense a criticism of the previous activities of the
Division. The CSIRO Executive had become convinced that the organization
should move into the field of human nutritional research and the
preferred laboratory to undertake such investigations was the
Division of Nutritional Biochemistry. Obviously the most appropriate
time to bring about such a change was when a new chief of Division
was to be appointed. Dick was naturally concerned about this decision
and particularly in respect of its possible effect on the future
of his staff.

Honours and Awards

Dick was admitted to the degree of Doctor of Science of the University
of Melbourne in 1954 and in the same year was awarded the University's
David Syme Research Prize (aeq). He was elected a Fellow of the
Australian Academy of Science in 1964, appointed an officer of
the Order of the British Empire in 1965 and in that same year
awarded a Senior Foreign Scientist Fellowship by the US National
Science Foundation.

Professional Activities

Dick was an active member of the Royal Australian Chemical Institute,
being admitted Associate in 1938 and Fellow in 1952. During the
period 1940-1945 he was secretary for three years of the Institute's
Biochemical Group and chairman for two years, and a member of
the Victorian Branch Committee in 1946. He was also involved in
other professional societies such as the Australian Society of
Laboratory Technology, of which he was successively a member of
council, vice-president and president and was elected honourary
life member. Likewise he was a foundation member of the Victorian
Society of Pathology and Experimental Medicine and became its
president in 1958.

acknowledgments

The writer acknowledges gratefully the very considerable assistance
provided by Mr H.J. Lee, formerly Senior
Principal Research Scientist of the CSIRO Division of Nutritional
Biochemistry, Dr C.C.J. Culvenor of the Division of Animal Health,
Mr J.B. Bingley, formerly of the Division of Animal Health, and
Mr Colin Smith, CSIRO Archivist.

Sir Robert Price
is a former Chairman of CSIRO and was, before that, Chief of its
Division of Organic Chemistry.

This memoir was originally published in Historical Records
of Australian Science, vol. 6, no. 3, Canberra, Australia,
1986.